Among the many people who have contributed to this study we wish to express our gratitude to the following: James W. Brackett, Philander Claxton, Arthur Devany, John Durand, Jason Finkle, Harald Frederiksen, Amos Haw-ley, Bert F. Hoselitz, Robert Hume, John Keppel, Howard J. Lewis, Juanita Mogardo, R. T. Ravenholt, Richard Reed, James Shannon, Alan Sweezy, Pauline Wyckoff, and George Zaidan. A special note of thanks must go to Mrs. Carol Picard and Mrs. Sharon Bauer, who ably helped with the organization and production of the study, and Mrs. Jane Lecht, who edited our manuscripts. IXto offer policymakers reasoned options and to demonstrate the qualitative as well as the quantitative dimensions of human population change. Current research is accumulating evidence that considerations of individual and family welfare have a direct and immediate impact on the fertility behavior of parents. Equally critical are the long-term considerations of the total number of people in relation to total food supply, resources, land, and the environment that transcend several generations, because they too must be the concern of the planner and policymaker today.